wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

Find the sum of the first 22 terms of an AP in which d=7 and the 22nd term is 149.


Open in App
Solution

Step 1: Find the first term of the series

Given that, common difference, d=7

22nd term, a22=149

Sum of the first 22term, S22=?

Using the formula ofnth term, we get

an=a+(n1)da22=a+(221)d149=a+21×7149=a+147a=2

Step 2: Find the sum of the terms

Sum of n terms,

Sn=n2(a+an)S22=222(2+149)S22=11×151S22=1661

Hence, the Sum of first 22 terms is 1661.


flag
Suggest Corrections
thumbs-up
25
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Geometric Progression
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon